Open-top refrigerated display case



Aug. 16, 1955 R. J. BURGER 2,715,321

OPEN-TOP REFRIGERATED DISPLAY CASE Filed May 1, 1952 Y mm 2 Sheets-Sheet l INVENTOR. 5040/7 L/ fiuryer Aug. 16, 1955 J BURGER 2,715,321

OPEN-TOP REFRIGERATED DISPLAY CASE Filed May 1, 1952 2 Sheets-Sheet 2 INVEN TOR. Ra/ph d Bur al 4/ BY W$W United States Patent OPEN-TOP REFRIGERATED DISPLAY CASE Ralph J. Burger, Kendallville, Ind., assignor to McCray Refrigerator Company, Inc., Kendallville, Ind., a corporation of Indiana Application May 1, 1952, Serial No. 285,407

2 Claims. (Cl. 6289.5)

This invention relates to open-top refrigerated display cases of the type used in food stores to display merchandise of a perishable nature for self-service.

The primary object ef the invention is to improve on the refrigerating action of cases of this character by so controlling the flow of refrigerated air into and through the open-top display compartment that the food products in said compartment are not only efliciently cooled but the cool air discharged into the compartment is protected against the disturbing action of air currents without the open top, thus enhancing the operation and commercial value of refrigerated cases of this type.

A further object of the invention is to discharge cold air into the open-top display compartment in a manner to produce two streams of different Velocities, the one of high velocity being employed to cool the produce in the compartment and the one of low velocity being directed across the top portion of the compartment above the high velocity air to serve as a protecting blanket therefor, whereby a more efi'icient and economical operation of the display case is obtained.

Further objects and advantages of the invention will be apparent from the following detailed description, and from the accompanying drawings illustrating one embodiment thereof, in which Fig. 1 is a front perspective view of a display case embodying the invention, with parts broken away, and Fig. 2 is an enlarged vertical section on the line 22 in Fig. 1, with a part broken away.

Referring to the drawings, 1 designates the front wall, 2, 2 the opposing end walls, 3 the rear wall and 4 the bottom of the case body, which parts cooperate to form an open-top chamber. This chamber is divided by a horizontal partition 5 into a lower compartment 6 and an upper open-top compartment 7.

The rear wall 3 at its top is provided with a forward extension 8 that overhangs the rear portion of the compartment 7 and has at its lower forward edge a downwardly projected nose portion 9 that terminates at a level slightly below the top level of the front wall 1, as is common with refrigerated cases of this character.

At the inner side of the rear wall 3 at the rear of the compartment 7 is an up flue 10 for cold air received, in the present instance, from the lower compartment 6. The upper end portion of this flue is divided by a vertical partition 11 into two separate discharge flues 12 and 13. The flue 10 and discharge flues 12 and 13 preferably substantially correspond in width to the length of the compartment 7 and both of the discharge flues direct their discharge forwardly and downwardly into said compartment. The partition 11 extends upward a short distance above the open discharge end of the flue 12 and then curves forwardly and downwardly on an 2,715,321 Patented Aug. 16, 1955 incline over said open end to provide a forwardly and downwardly directed discharge for said flue.

The rear wall 14 of the flue 10 extends above the level of the curved forward extension of the partition 11 and then extends upward and forward on an incline on the bottom surface of the wall portion 8, as at 15, and then downwardly and forwardly, as at 16, to the nose 9 which is located above and forward of the upper forward edge of the partition 11. This provides an air discharge opening 17 for the flue section 13 that is considerably wider vertically than the discharge opening from the flue section 12. Also the throat or cross-sectional size of the flue section 12 is less than that of the flue section 13 and the mouth portion of the flue 13 is considerably larger in area than that of the flue. This latter provides the flue 13 with an expansion chamber 18 at its discharge end whereby the force of discharge of cold air into the compartment 7 from the flue section 13 is reduced over that of the air discharge from the flue section 12. This is important and is the feature in which the present invention particularly resides. The discharge opening 17 is preferably screened as shown at 17 to effect a diffusion and retardation of air discharging therethrough.

The compartment 7 at its front side throughout its length is provided with a down flue 20 formed by a plate 21, preferably of glass, set in spaced preferably inclined relation to the front wall 1. The air inlet opening at the top of this plate is spaced below the top of the front wall and is preferably a short distance below the level of the discharge opening 12 of the front flue section 12.

The flue 20 has a narrow inlet and widens downwardly therefrom to the bottom of the compartment 7 due to the inclination of the plate. The lower end of the flue 20 opens into the forward top portion of the bottom compartment 6 where it passes through one or more openings 23, in the present instance two in number, into a plenum chamber 24 and from the rear of such chamber to contact with a set of cooling coils 25 of a refrigerating system. The box or frame 26 in which the coils are disposed extends throughout substantially the length of the compartment 6 and is open at its front to the plenum chamber 24 and at its rear to the open end of the up flue 10. An electrically driven fan 27 is mounted in each opening 23 to set up a forced circulation of air rearward therethrough.

Produce supporting trays 30 are suitably supported in the bottom portion of the compartment 7 in spaced relation to the partition 5 to provide a space 31 therebetween, and these trays are perforated or foraminous to permit drainage and the passage of air therethrough to said space. Air may have a metered discharge from the space 31 into the front down flue 20 through a series of small openings provided in the front wall of said space. This feature and its advantage are fully described in a co-pending application Serial No. 70,555 and no claim therefor is made herein.

The partition 5 is preferably mounted to permit access to the parts located in the bottom compartment 6 of the case, and in the present instance is shown as having its front and rear edges provided with down-turned flanges 33 adapted to rest at front in a channeled flange 34, and at rear in a channeled flange 35 on the lower edge of the flue plate 36.

A comparison of the operating efliciency of this case with that of a similar case, except that only a single stream of cold air is discharged into the top of the chamber 7, showsa marked improvement in the pres- I wish it understood that my invention is not limited to any specific construction, arrangement or form of the parts, as'it is capable of numerous modifications and changes-Without departing from the spirit of the claims.

Having thus described my invention, what I claim as new, and desire to secure by United States Letters Patcut, is:

1. In a refrigerator cabinet having an open-top compartment and an air chamber therebelow with a return air flue from said compartment to said chamber at one side of the compartment with its inlet near the top thereof substantially throughout its length, and with an upwardly extending air outlet flue at the opposite side of said compartment to said return flue, and means for creating an air circulation through said fines and cooling the air passing through said outlet flue, the improvement which comprises the provision in at least the upper end portion of said outlet flue, of a partition dividing said portion of the flue into inner and outer branches relative to said compartment, said inner branch having discharge provision at its upper end for directing a stream of air across the upper portion of said compartment toward said return flue inlet and said other branch having a pressure reducing expansion chamber at its upper end for the expansion of air received from said outlet flue and having an opening forthe discharge of a stream of air from such chamber over said first stream and toward said return flue inlet whereby a stream of low velocity cold air from said expansion chamber forms a protecting blanket entirely across said compartment over a stream of cold air of relatively higher velocity from said inner branch.

2. In a refrigerator cabinet having an open-top compartment and an air chamber therebelow with a return air flue from said compartment to said chamber at one side of the compartment with its inlet near the top thereof substantially throughout its length, and with an upwardly extending air outlet flue at the opposite side of said compartment to said return flue, and means for creating an air circulation through said lines and cooling the air passing through said outlet flue, the improvement which comprises the provision in at least the upper end portion of said outlet flue, of a partition dividing said portion of the flue into inner and outer branches relative to said compartment, said inner branch having discharge provision at its upper end for directing a stream of air across the upper portion of said compartment toward said return flue inlet and said other branch having a pressure reducing expansion chamber at its upper end for the expansion of air received from said outlet flue and having an opening for the discharge of a stream of air from such chamber over said first stream and toward said return flue inlet whereby a stream of low velocity cold air from said expansion chamber forms a protecting blanket entirely across said compartment over a stream of cold air of relatively higher velocity from said inner branch, and a screen across the discharge opening from said expansion chamber to diffuse and retard the discharge of air therefrom.

References Cited in the file of this patent UNITED STATES PATENTS 2,050,063 Millott Aug 4, 1936 2,421,314 Brinkoeter May 27, 1947 2,594,066 Pabst Apr. 22, 1952 2,613,507 Pabst Oct. 14, 1952 2,613,508 Brinkoeter Oct. 14, 1952 2,626,508 Bently Jan. 27, 1953 2,641,111 Bishop June 9, 1953 

